Contact for electric knife switches



Apr. 1*, 1923 W.- J. GIBBQNS CONTACT FOR ELECTRIC KNIFE SWITCHES Filed Mar.

INVENTQR.

ATTORNEY.

Patented A r. to, 1923.

ST YEE iti iil'it il CONTACT FOR ELECTRIC KNIFE SWITtIHFiS.

Application fi1ed March 21, 1921.

To all whom it may camera:

e it known that 1, WILLIAM J. GrnnoNs, a citizen of the United States. and a resident of Phiiadel hia,-in the county of Philadelphia and tate of Pennsylvania, have invented an Electric Knife Switches. ofwhich the following is-a specification.

y invention relates to improvements in contacts for electric knife switches, and it has for one of its objects to provide a contact for such switches which, as far as I am aware, will retainits eificiency for a much longer period than contactsof like character as heretofore constructu.

A further object it to portions thereof will not, incident to use, become permanently separated to such an extent that the knife contact member of a knife switch will not make satisfactory: contact therewith.

A further object to provide a contact of the character stated inwhich the opposite side portions of said contacts are so interlocked or connected together that when the knife contact} is inserted between the contact portions eitch will exert a pull upon the other. The pulling action of the opposite side portions of the contact structure will be exerted in opposite directions with the result that when the knife contact is inserted a more perfect contact is made.

A still further object of my-invention is to in which the opposite contacting portions of the contact device the opposing portions contact device.

Other objects and advantages of my invention will be pointed but in detailed description thereof which follows or will be apparent from such description.

In order that the invention may be more readily understood and its practical advantages fully appreciated reference may be had to t e accompanying drawing in Fig. 1" is a perspective view of one type of contact device embodying my invention; ig. 2 is an ,end elevation thereof showing 1n position between the contact/ portions of the said contact device;

Improvement in Contacts for on the line 6-6 of provide a contact electrical contact device; of the character stated in which the contact jacently These portions are arranged in substantially parallel relation with the said parts 5 and cross section afkni fecontact member in. p

:and 13. *Th

Serial No. 453,950.

on the line 3-3 of Fig. I;

Fig. tie a perspective view showing a modified construction of contact device of the same type as that shown in the preceding figures, a portion of the said device being broken away;

Fig. 5 is a view in end'elevation of the device shownin F at and showing also in cross section a knife contact in place be tween thecontacting portions of said device;

Fig. 6 is a transverse sectionai view'taken Fig. 4%;

Fig. 7 is a perspective view showing invention embodied in another type Fig. 3 is a transverse scctir inal view taken Oi Fig. 8 is'a view in edge device shown in Fig. Q'and showing also in cross section the knife contact in place between the contact portions of the said device; and I Fig. 9 is a vertical sectional view the line 9 of Fig. 7.

\eferring to the drawing: the base portion of of which the said devices are connected to supports by screws or other fastening means which pass through openings 2. Referringnow to Figs. '1 to 3 inclusive, 3 and 3 designate the opposite sides of the spring plate contact devices which sides extend rlpwardly and converge toward each other as shown.- The these sides are bent inward-i3). as indicated at 4, a'.d then downwardly to form adsituated contact portions 5 and 6.

taken on 1 designates respect to each other, and the distance between the same is less than the thickness of the knife contact thember 7, shown in Figs. 2 and 3. In the use of these tions5 and fi-and the opposite sides 3 and 3, are sprung apart upon the insertion between 6 of the knife contact contact devices by means elevation of the upper end portions cit contact devices, the contact pormembers 7. In order to retain the parts 5- and 6 in parallel relation to each other and in order to prevent impairment of the usefulness of the device by reason of the contact portions. 5 and 6, assuming permanent positions at too. great a distance from each other, I have provided the hook shaped projections 10 and 11 which are formed by slitting the sides 3 and 3 as indicated at 12 e portions thus separated from the respective sides at the opposite ends of the device are then-bent so as to form the said hooks and 11. The hook 10 carried by the side 3 of the device extends trans- 'versely of the device underneath the lower ends of thecontact portions Hand 6 and upwardlyupon the outer side of the contact portion 6, the lower outer edge of the latter contacting with the inner surface of the said label; 10. p

1 The hook 11 carried by the side-3 extends transversely of the device in a direction op I posite to that of the hook 10 and passes underneath the. lower ends of the contact iii positely projections and 21 which aresituated at the opposite ends or edges of the device as l shown in Fig; 4. Each of these tongue-like portions is bent to form hooks, as indicated at 22 and 23, which hooks engage the outer sides of the parts 18 and 19, as shown. The

hook 22, which projects from and is carried by thecontact portion 18, extends underheath the lower end of the contact portion 19 and then upwardly and into contact with the outer side of the lower portion thereof. Likewise the tongue portion 2'1, connected with and carried by the contact portion 19.. extends transversely underneath the lower end of the contact portion ls and-thenup f .wardiy, as indicated at 23, and into contact.

with the outerside'of the lower portion of the contact part 18? The contact device shownjn Figs. 1 to 6 inclusive is known as the roll type. I

In 'Z'to 9 inclusive 1 have shown the inventicnembodi'ed in another. type of conconstructions tact-device in which the upper end portions- -of the opposite sides thereof are not bent or as in the case (if-the previous ln'thesaid Figs. 7 to 9 inclusive, the opposite sides of the device comprise ortions 30' and 31 which converge somew at sharply toward each other and-arc merged into the .less convergent upwardly extending contact portions 32 and 33. r The extreme upper ends of the opposite sidepon' rolledinwardly tions of'this type of device are'bent' out-'- wardly' as indicated at 34 and 35 so as to facilitate the entry'of the knife contact rnem- I ber 36 between the opposite contact side por tions 32 and 33. Each of the sides 32and 33 is provided'with tongue-iike portions 37 and 38 which are bent form hool s39'and a0.

ried by the side converging part 30 -will be observed that the hooks 39 and 40 terrace The hook 39 which is connected to and car- 32 extends through a rectangularly-shaped notch formedat'one edge of the converging side portion 31 adjacent the point of connection between the said portion 31'and the portion 35. The hook 40 extends through a corresponding notch 46 through the opposite edge portion of of the contact device. It

engage the outer sides of the oppositely disposed contact portions and of the device.

it will be observed that in the several forms ofconstruction the presence of the hooks in contact with the outer sides of the oppositely disposed contacting portions of the contactdevices offers opposing resistance to the separation of the Contact devices upon the insertion of a knifecontact member bethe tween'the same. Referring for instance'to Figs. 1 to 3, itwill be observed that upon the insertion of a'knife contact member between the opposed contact portions 5 and 6,

the'latter will be caused to slightly separate.

and 11. ll henthe contact portionfitends to move toward the left pressure is exerted upon the hook 10 and the force of such pressure is transmitted to the side 3; likewise the contact portion 5 tends ,to mo-W toward the right, such movement being resisted by the hook ll and the iorcc resulting tram, such resistance is transmitted to the smiefi consequence of this arrangement it will be seen that-the hooks, which engage the outer sides of the oppositely disposed contact portions, tend to cause closer contact of the said portions with the opposite sides of the knife contact members.

inclusive are not carried directly by the op posite sides-15 and 16, yettheir presence effects substantially the same res'ult as is efi'ected by'the hooks shown in the construc-- tions illustrated in Figs. 1 to 3 inclusive and 7 to 9 inclusive.

v A further object of a construction embodying my invention is that the contact portions thereof are prevented from assuming permanent positions a relatively great distance apart, with the result that upon -Althoug'h the hooks s2 and 23 shown in I the construction illustrated, inFigs. 4 to 6 the'placing of a knife contact member between the said contact portions it makes complete and close contact therewith from the very moment that it begins its entry between the said'parts also the said close con tact is maintained until the very moment the said knife contact member passes from between the said contact portions. If this relationship between the oppositely disposed contact portions of the said device andthe knife contact member is not maintained .a relatively great amount ofsparking takes its m This separation is resisted by the hooks 1O I place upon removing it from between the said portions, thus causing unnecessary impairment of the said device,

Although I have shown my invention as applied to spring plate contact devices-0t the character shown for electric knife switches, it will be understood that the prinaiple of my invention is applicable to other constructions where. it is desirable that close contact relationship shall be maintained between electrical contact devices; also that the contact devices may consist of other material than spring plate, as for instance, spring wire.

Having thus described my invention, what I claim and desire to secure by Letterslatout is: I

1. An electric contact device comprising oppositely disposed side portions and separate means carried by'each portion for engaging the other portion. the said means tending to prevent separation of said por tions.

2. An electric contact device comprising oppositely disposed side portions and a hook projecting from each side portion of said device and engaging vthe opposing contact portions of said device.

3. An electriccontact device comprising oppositely disposed yielding side portions; and means having integral connection with each side portion and engaging the other side portion, and said means tending to prevent separation of said side portions.

4. An electric contact device comprising oppositely disposed side portionsQand two separate means, one carried by one side portion and the other by the other side portion, interlocking and connecting the said portions so that upon the insertion of a contact member between the opposing contact parts of said portion each portion will exert a pulling force upon the other,'the said forces tending to pull the said opposite side portions toward each other.

r 5. An electric contact device comprising a base portion, convergingside portions eittending upwardly from the opposite ends of said base. portion, oppositely disposed contact portions carried by said converging side portions, means carried by each side portion and extending transversely of the said device and beyond the contact portion of the opposing vside and being in engagement providing depending substantially parallel contact portions intermediate the said side portions, andhooks carried by said side por- Lions and being in engagement with the outer sidesof said contact portions and resisting separation of said contact portions when the knife member of such switch is inserted between the same 7. A contact device foran electric knife switch comprising a baseportion. side portions extending upwardly from said base portion, the upper ends of said side portions extending inwardly and downwardly, intermediate said side POI'tlOIlS, thedown-- wardlv extending end portions constituting oppositely disposed contact portions. hooks having integral connection with said side portions, the hook upon one of said. side portions being situated at one end of the contact device and the hook upon the other side portions being situated at the other end of said device, and-the said hooks extending transversely of the said device and underneath the lower ends of said contact portions and contacting with the outer-sides of said portions, substantially as described.

8.A contact device for an electric, knife switchcomprising a base portion, side portions extending upwardly from said base portion, the upper ends of said side portions extending inwardly and downwardly intermediate parts of the said side portions, the downwardly extending portions constitutingoppositely disposed contact portions and each of the said contact portions having hook. extensions, the hoolc upon one. of

said contact portions engaging the outer side of the other contact portion.

- In testimony that I claim the foregoing as my invention l have hereunto subscribed my name this'l'i day of March, 1921..

WILLIAM J. om'BoNs. 

